Are Kristen Stewart + Zac Efron Hooking Up?

Even though Kristen Stewart was rumored to be back together with longtime rollercoaster love Robert Pattinson, a brand new name has entered the romantic mix from left field: Zac Efron. Is 'Twilight' mixing with 'Hairspray?'

Sources told Star that K-Stew wanted a piece of Zefron because she knew he'd keep it light.

"Kristen's relationship with Rob was so tense," the insider said (via Entertainment Wise). "She's ready to have a good time, and wants to date a completely different type of guy."

The source said Efron fits the bill, especially considering he hasn't been in a serious relaysh since he and 'High School Musical' co-star Vanessa Hudgens split. "He's a bit of a playboy," the source said of Efron. "So he wants to keep his partying lifestyle intact. He's not looking for anything emotional, and Kristen doesn't want anything serious. This could work out great for both of them."

Yeah, if it were true.

Sources close to K-Stew insist there's nothing up with the 'Lorax' star.

"Kristen, like every other girl in the world, thinks that Zac Efron is hot but she isn't actively pursuing him," the insider dished to Hollywood Life.

Why not? "He's actually too buff. She likes skinnier and more the hipster type of guys. Don't hold your breath for this relationship to ever happen."